Fixed-amount spray type aerosol container

ABSTRACT

A fixed-amount spray type aerosol container in which stem rubber is pressed against a mounting cap by a spring provided below the stem connected to a nozzle, and a tank is fixed between a guide bush that fixes the stem rubber and a housing, the container including a valve with a shape stabilizer installed between the guide bush and the tank. The container is nearly free from entry of external air and can spray the contents at a nearly constant amount until the contents nearly run out.

FIELD OF THE INVENTION

The present invention relates to a fixed-amount spray type aerosolcontainer. More specifically, the present invention relates to afixed-amount spray type aerosol container which is filled withcompressed air and which can inject the contents therein at a nearlyfixed amount almost every time, even if fixed amount spray type aerosolcontainer is used repeatedly.

BACKGROUND OF THE INVENTION

Hitherto, in order to allow the active ingredients that give tastes,drug effects and similar to directly act on a desired portion such asnasal cavity, palate, oral cavity, pharynx and tongue, such process isdesigned so that the active ingredients are liquefied and filled in aso-called nebulizer type finger-pressing air pump, and the liquefiedactive ingredient is sprayed over a desired portion in the oral cavity.

However, the nebulizer type finger-pressing air pump has problems that,because a nozzle moves vertically in operating the air pump, it isextremely difficult to precisely spray the active ingredient onto aspecific portion only, and in addition, when the nozzle is restored tothe original position, the external air is sucked into the air pump,creating a fear that the inside of the air pump is contaminated byvarious germs present in air.

Therefore, for a method to allow active ingredients to directly act on aspecific portion, investigation has been made on a method for fillingactive ingredients in an aerosol container and spraying the activeingredients over the specific portion. However, since the activeingredients are continuously sprayed when an aerosol container is used,the active ingredients attach to the specific portion in largequantities, whereby generating side effects or wasting the activeingredients.

Therefore, under these circumstances, the present inventors made earnestefforts to develop products which can precisely give active ingredientsto a desired portion, and at the same time is free from entry of airoutside the product into the inside thereof and ensures high sanitation,and further is able to spray the active ingredients of a fixed amountusing compressed gas, and finally have found such products and havecompleted the present invention.

SUMMARY OF THE INVENTION

That is, the present invention relates to a fixed-amount spray typeaerosol container in which a stem rubber is pressed against a mountingcap by a spring provided below a stem connected to a nozzle, and a tankis fixed between a guide bushing that fixes the stem rubber and ahousing, the container including a shape stabilizer installed betweenthe guide bushing and the tank.

The fixed-amount spray type aerosol container of the present invention,includes the combination of: a container body having an openingtherethrough leading to a chamber therein; a housing having a main bodyportion and a flange, wherein the flange is supported on the opening ofthe container body and the main body portion hangs suspendedly throughthe opening in the chamber of the container body; a gasket between anouter surface of the housing and an inner surface of the container body;mounted over the opening in the container body so as to be in contactwith the flange of the housing; a stem having first and second ends,wherein the first end projects out of the container body through anopening in the mounting cap and the second end projects into thecontainer body within the housing; a stem rubber fitted around the stem;a spring fitted around the second end of the stem and pressing the stemrubber to the mounting cap; a nozzle attached to the first end of thestem; a dip tube connected to the housing within the chamber of thecontainer body; a guide bushing located between the stem and thehousing; a tank, having a bottom portion and a side wall, is locatedbetween the guide bushing and the housing, wherein the tank is supportedby the housing so that the bottom portion of the tank makes sealingcontact with the housing and the side wall of the tank is pressedradially inwardly by a pressure of a gas charged in the container body;facilities for stabilizing a shape of the tank, wherein the shapestabilizer facilities are located at spaced intervals between the guidebushing and the tank; and a fixed-amount chamber formed between theguide bushing and the tank.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic sectional view of a fixed-amount spray typeaerosol container according to the present invention when not in use;

FIG. 2 is a schematic sectional view of a fixed-amount spray typeaerosol container according to the present invention in operation;

FIG. 3 is a sectional view taken along the line A--A of the fixed-amountspray type aerosol container according to the present invention in FIG.1;

FIG. 4 is a sectional view taken along the line A--A of FIG. 1 showingan example of another shape stabilizer used for the fixed-amount spraytype aerosol container according to the present invention;

FIG. 5 is a graph showing the relationship between spray frequency andspray amount and internal pressure when the fixed-amount spray typeaerosol obtained in Example 1 according to the present invention isused; and

FIG. 6 is a graph showing the relationship between spray frequency andspray amount and internal pressure when an aerosol container obtained inComparative Example 1 according to the present invention is used.

DETAILED DESCRIPTION OF THE INVENTION

The fixed-amount spray type aerosol container according to the presentinvention will be described in detail referring to the attacheddrawings.

FIG. 1 is a schematic sectional view showing an embodiment of afixed-amount spray type aerosol container according to the presentinvention at a steady state (at a or when not in use).

A nozzle 1 is connected to a stem 2, and a stem rubber 4 is pressedagainst a mounting cap 5 by a spring 3 provided below the stem 2. Acontainer body 6 is sealed and fixed between the mounting cap 5 and agasket 7, whereby the aerosol container is kept under a hermeticallysealed condition.

To the outer periphery of a guide bushing 8 which fixes the stem rubber4, is provided a tank 9 is provided comprising material withflexibility, for example, natural rubber, synthetic rubber such asnitrile rubber (NBR), butyl rubber (IIR) and silicone rubber, elastomer,soft plastics or similar, and the tank 9 is fixed by a housing 10. Tothe bottom surface of the housing 10, a dip tube 11 is connected. Forthe tank 9, it is desirable to use silicone rubber because activeingredients are not absorbed or decomposed.

The contents filled in the aerosol container enter the housing 10 viathe dip tube 11, and enter the inside of the guide bushing 8 via aclearance between the stem 2 and the tank 9 as well as a clearancebetween the stem 2 and the guide bushing 8. The contents then fill afixed-amount chamber 13 formed between the guide bushing 8 and the tank9 via a hole 12.

Pressing the nozzle 1 downwards can activate the aerosol container asshown in FIG. 2.

The contents in the aerosol container enter the housing 10 via the diptube 11, but since a clearance between the bottom of the stem 2 and thetank 9 is completely sealed, the contents are not introduced into theguide bushing 8.

Because internal pressure of the aerosol container is greater thanexternal pressure (atmosphere) thereof, when the nozzle 1 is presseddownwards and a guide hole 14 of the nozzle 1 is brought in freecommunication with the fixed-amount chamber 13 via a guide hole 15 andguide bushing 8, the tank 9 deforms as shown in FIG. 2 by the pressureof the contents in the aerosol container introduced via thecommunicating hole 16, and the contents in the fixed-amount chamber 13are sprayed from a spray hole 17 via the hole 12 and guide holes 15 and14, successively.

In the present invention, a shape stabilizer 18 is provided between theguide bushing 8 and the tank 9. Thus, when the contents are sprayed fromthe spray hole 17, the tank 9 deforms nearly uniformly and the shape ofthe tank 9 is stabilized, and the tank 9 does not deform unevenly as inthe case when the shape stabilizer 18 is not provided, whereby enablingrepeated fixed-amount spray of the contents.

In FIG. 1 and FIG. 2, the shape stabilizer 18 is formed as a so-calledrib on the outer periphery of the guide bushing 8, and the shape of theshape stabilizer 18 is not particularly limited, but examples include aquadrate prism, semicircular cylinder, and similar. In order to deformthe tank 9 into an orderly shape, it is desirable not to provide aclearance between the shape stabilizer 18 and the tank 9 as shown inFIG. 1 and FIG. 2. If the number of the shape stabilizer 18 locatedbetween the guide bushing 8 and the tank 9 is excessively small, thetank 9 is difficult to uniformly deform, while if it is excessivelylarge, the deformation amount of the tank becomes small to lessen thespray amount of the contents. It is, therefore, desirable to locateshape stabilizers, in general, at 3-16 places, though it depends on theshape of the shape stabilizer 18.

FIG. 3 shows a fractured surface at section A--A of FIG. 1.

In FIG. 3, the shape stabilizer 18 is formed at five places as so-calledribs on the outer periphery of the guide bushing 8 as described before.In this way, in the present invention, the shape stabilizer 18 might beprovided on the outer periphery, and as shown in FIG. 4, it might not beprovided on the outer periphery of the guide bushing 8, but might beprovided on the inner periphery of the tank 9.

In addition, another member might be inserted and formed between theguide bushing 8 and the tank 9 in the form of a so-called spacer.

As stated above, when the fixed-amount spray type aerosol containeraccording to the present invention shown in FIG. 1 and FIG. 2 is used,the tank 9 always deforms in a nearly constant shape, enabling thecontents to be filled in the fixed-amount chamber 13 to be sprayed tothe outside via the spray hole 17 of the nozzle 1 in a fixed amount.

Because the fixed-amount spray type aerosol container according to thepresent invention can spray the contents to the outside in a fixedamount not only when liquefied gas such as LPG is used for a sprayagent, but also even when compressed gas such as air, N₂, CO₂ or N₂ O isused, it provides an advantage of being used for a wide range of variousapplications.

The fixed-amount spray type aerosol container according to the presentinvention will be described in further detail by way of examples, butthe present invention shall not be limited to such examples.

EXAMPLE 1

4 grams of purified water and 12 grams of glycerin were placed in acontainer body (full filling volume: 28 ml), and using sterilizedcompressed air as a spray agent, the container body was filled with themso that the internal pressure achieved 6.0 kg/cm² at 25° C. Using thevalve (shape stabilizers were arranged at 5 places) shown in FIG. 1 andFIG. 2, the valve and a nozzle were attached to the container body tomake an aerosol product.

The contents (purified water and glycerin) were sprayed through thenozzle from the aerosol product obtained, and the change of spray amountand internal pressure were measured. The results are shown in FIG. 5.

The results shown in FIG. 5 indicate that when the fixed-amount spraytype aerosol container was used, as shown in Graph A, the contents couldbe sprayed at a nearly constant amount until the contents scarcelyremained in the container, and as shown in Graph B, even if there was afluctuation in internal pressure, the change of the spray amount wassmall.

COMPARATIVE EXAMPLE 1

In Example 1, an aerosol product was made in the same manner as in thecase of Example 1 except that shape stabilizers were removed.

From the aerosol product obtained, the contents were sprayed through thenozzle, and the change of spray amount and internal pressure weremeasured. The results are shown in FIG. 6.

The results shown in FIG. 6 indicate that the aerosol container obtainedin Comparison 1 greatly decreased the spray amount as the sprayfrequency increased as shown in Graph A as the internal pressure variedas shown in Graph B.

Comparison between Example 1 and Comparative Example 1 indicates thatthe fixed-amount spray type aerosol container of Example 1 with shapestabilizers provided between the guide bushing and the tank can spraythe contents at a fixed amount until the contents nearly run out.

The fixed-rate spray type aerosol container according to the presentinvention provides an effect that it is nearly free from entry ofexternal air and it can spray the contents at a nearly constant amountuntil the contents nearly run out.

INDUSTRIAL APPLICABILITY

The fixed-amount spray type aerosol container according to the presentinvention can spray the contents nearly at a fixed amount, even if it isfilled with compressed gas and is repeatedly used, so that it isparticularly useful for an aerosol container for spraying liquid activeingredients into the oral cavity.

We claim:
 1. A fixed-amount spray type aerosol container comprising:acontainer body having an opening therethrough leading to a chambertherein; a housing having a main body portion and a flange, wherein saidflange is supported on said opening of said container body and said mainbody portion hangs suspendedly through said opening in said chamber ofsaid container body; a gasket between an outer surface of said housingand an inner surface of said container body; a mounting cap mounted oversaid opening in said container body so as to be in contact with saidflange of said housing; a stem having first and second ends, whereinsaid first end projects out of said container body through an opening insaid mounting cap and said second end projects into said container bodywithin said housing; a stem rubber fitted around said stem; a springfitted around said second end of said stem and pressing said stem rubberto said mounting cap; a nozzle attached to said first end of said stem;a dip tube connected to said housing within said chamber of saidcontainer body; a guide bushing located between said stem and saidhousing; a tank, having a bottom portion and a side wall, is locatedbetween said guide bushing and said housing, wherein said tank issupported by said housing so that said bottom portion of said tank makessealing contact with said housing and said side wall of said tank ispressed radially inwardly by a pressure of a gas charged in saidcontainer body; means for stabilizing a shape of said tank, wherein saidshape stabilizer means are located at spaced intervals between saidguide bushing and said tank; and a fixed-amount chamber formed betweensaid guide bushing and said tank.
 2. The fixed-amount spray type aerosolcontainer of claim 1, wherein said shape stabilizer means are aplurality of radially extending ribs which are integral with any one ofan outer periphery of said guide bushing and an inner periphery of saidtank.